Four channel pipetting arm



FIG. 1 is a front, bottom, left perspective view of a four channel pipetting arm showing our design therefor;

FIG. 2 is a left side elevational view thereof;

FIG. 3 is a right side elevational view thereof;

FIG. 4 is a front elevational view thereof;

FIG. 5 is a rear elevational view thereof;

FIG. 6 is a bottom plan view thereof;

FIG. 7 is a top plan view thereof; and,

FIG. 8 is a rear, top, left perspective view thereof.

The broken lines in the drawings depict portions of the four channel pipetting arm and form no part of the claimed design. 

CLAIM The ornamental design for a four channel pipetting arm, as shown and described. 